Ed Davey, the Liberal Democrats' home affairs spokesman, said it was pointless changing laws when there were too few officers.

He warned: "Thinking new stop and search powers will help ignores the evidence, is frankly a derisory response to criminal threats from hi-tech drones and lasers, and is a distraction from the real challenge of rebuilding community policing.

"Only a long-term financial commitment to community policing will restore the trust in police that is so vital to fighting crime, whilst a disproportionate use of stop and search can undermine that very trust community police officers rely on."

A Home Office spokesperson said: "As outlined in the serious violent crime strategy we are looking at ways to strengthen police powers to identify individuals carrying corrosive substances."